Answer:
-77 + (-46)
=> -77 - 46 (When you add two negative integers, it is the same thing as subtracting a positive integer with a negative integer)
=> -123 (Because a negative + a negative = a negative)
If my answer helped, kindly mark me as the brainliest!!
Thank You!!
= -77 + ( - 46 )
= - 77 - 46 ( a positive integer and a negative integer makes a negative integer )
= -123 ( two negative signs resulted in the usage of addition )
Therefore , -77+ (-46) = -123
Solve the following quadratic equation by factorising: 15x^2 + 2x - 8 = 0
Some transportation experts claim that it is the variability of speeds, rather than the level of speeds, that is a critical factor in determining the likelihood of an accident occurring (Update, Virginia Department of Transportation, Winter 2000). One of the experts claims that driving conditions are dangerous if the variance of speeds exceeds 75 (mph)2. On a heavily traveled highway, a random sample of 55 cars revealed a mean and a variance of speeds of 62.5 mph and 94.7(mph)2, respectively. (You may find it useful to reference the appropriate table: chi-square table or F table)
1. Set up the competing hypothesis to test wxpert,s claim.
2. At the 5% significance level find the critical value and state the decision rule.
3. Can you conclude that driving conditions are dangerous on this highway? explain.
Answer:
Explained below.
Step-by-step explanation:
The claim made by an expert is that driving conditions are dangerous if the variance of speeds exceeds 75 (mph)².
(1)
The hypothesis for both the test can be defined as:
H₀: The variance of speeds does not exceeds 75 (mph)², i.e. σ² ≤ 75.
Hₐ: The variance of speeds exceeds 75 (mph)², i.e. σ² > 75.
(2)
A Chi-square test will be used to perform the test.
The significance level of the test is, α = 0.05.
The degrees of freedom of the test is,
df = n - 1 = 55 - 1 = 54
Compute the critical value as follows:
[tex]\chi^{2}_{\alpha, (n-1)}=\chi^{2}_{0.05, 54}=72.153[/tex]
Decision rule:
If the test statistic value is more than the critical value then the null hypothesis will be rejected and vice-versa.
(3)
Compute the test statistic as follows:
[tex]\chi^{2}=\frac{(n-1)\times s^{2}}{\sigma^{2}}[/tex]
[tex]=\frac{(55-1)\times 94.7}{75}\\\\=68.184[/tex]
The test statistic value is, 68.184.
Decision:
[tex]cal.\chi^{2}=68.184<\chi^{2}_{0.05,54}=72.153[/tex]
The null hypothesis will not be rejected at 5% level of significance.
Conclusion:
The variance of speeds does not exceeds 75 (mph)². Thus, concluding that driving conditions are not dangerous on this highway.
To determine whether or not they have a certain desease, 304 people are to have their blood tested. However, rather than testing each individual separately, it has been decided first to group the people in groups of 19. The blood samples of the 19 people in each group will be pooled and analyzed together. If the test is negative, one test will suffice for the 19 people (we are assuming that the pooled test will be positive if and only if at least one person in the pool has the desease); whereas, if the test is positive each of the 19 people will also be individually tested and, in all, 20 tests will be made on this group. Assume the probability that a person has the desease is 0.04 for all people, independently of each other, and compute the expected number of tests necessary for the entire group of 304 people.
Answer:
The expected number of tests necessary for the entire group of 304 people is 180.0325
Step-by-step explanation:
Probability of person being positive = p = 0.04
Probability of person being negative = q = 1-0.04=0.96
Number of people in each group = 19
We will use binomial over here
Probability of no test positive :
[tex]P(x=0) = ^{19}C_0 (0.04)^0 (0.96)^{19} =0.460419201958[/tex]
P( at least one tests positive) = 1-P( no one tests positive)= 1-0.460419201958= 0.539580798042
Expected number of tests for each group = 1(0.460419201958)+20(0.539580798042) = 11.2520351628
Number of groups =[tex]\frac{\text{Total population}}{\text{no. of people in each group}}=\frac{304}{19}=16[/tex]
Expected number of tests necessary for the entire group of 304 people:
=[tex]\text{Expected number of tests for each group} \times \text{No. of groups}[/tex]
=[tex]11.2520351628 \times 16[/tex]
=180.0325
Hence The expected number of tests necessary for the entire group of 304 people is 180.0325
why? just why. why are we here? should i off myself? should i stay?
Answer:
It can be a passing thought or a question that launches a full-on existential exploration. Having a sense of meaning and purpose in life is usually a positive motivator, at home and at work. But maybe the questioning itself is where life's true mission is found...
Step-by-step explanation:
What is the sum of the fractions? Use the number line to help find the answer.
3/5 plus -7/5
Answer:
-4/5
Step-by-step explanation:
Answer:
The answer is -4/5
Step-by-step explanation:
Hope this helps!:)
Write the ratio 26 to 24 as a fraction in simplest form.
Answer:
13:2
Step-by-step explanation:
26 to 24 = 26/24 can further be simplified to 13/12
13/12 = 13:12
Plz mark as brainliest, I am close to expert.
Which of the statements below summarize why a buyer would desire a purchase allowance? (Check all that apply.)
In order to keep defective, but still marketable merchandise, the buyer would need a reduction in the purchase price.
Purchased merchandise was defective or unacceptable.
The buyer purchased a large amount of merchandise and was eligible for a reduced purchase price.
The seller could not pay within the discount period.
Answer:
First two options correct
Step-by-step explanation:
I got it from answer key
An ion formed from an atom has a 1- charge. The number of electrons present in the ion is 36 and the number of neutrons is 46. Identify the element by typing the name. For example: Hydrogen or Sodium.
Answer:
Write and interpret symbols that depict the atomic number, mass number, and ... The amu was originally defined based on hydrogen, the lightest element, then later in terms of oxygen. ... The electron has a charge of 1− and is a much lighter particle with a mass of ... (b) the ion with 36 electrons, 35 protons, and 45 neutrons.
Step-by-step explanation:
You have been asked to order a three-layer cake for the party. In order to feed 75 people, the bakery gave you the following two options for the size of each layer:
Option 1: Option 2:
Layer 1 - 10-inch diameter Layer 1- 11-inch diameter
Layer 2 - 8-inch diameter Layer 2- 7-inch diameter
Layer 3 - 6-inch diameter Layer 3- 4-inch diameter
Each layer is shaped like a cylinder and will have a height of 4 inches. The bakery charges $0.50 per cubic inch of cake.
What is the total cost of cake Option 1?
What is the total cost of cake Option 2?
Must show work and formulas
Answer:
1-11-2-7-3-4-0.50 =-26.5
Step-by-step explanation:
You have wanted a car you entire life (literally since you were born)!! It is time...you found the car of you dreams AND the car is marked as 80% of!!!! What a deal!!! "What could go wrong" you ask yourself. You buy the car for $625 (and the man in the hood walks off smiling). As your parent(s) drive you home after picking you up next to your broken down vehicle 3 hours later, they ask you what the original price of the car was before the price reduction. What was the original price of your.... "dream car"?
Answer:
200,000
Step-by-step explanation:
how do i solve intervals
Which statement is correct?
Answer:
c is correct
Step-by-step explanation:
Brainly Crown Pls
Round 1,439 to the nearest ten
Answer:
1,440.
Step-by-step explanation:
39 is closer to 40.
1,400 is unchanged.
Jasmine walks three dogs after school. She brings dog
treats for the dogs. She gives 4 treats to Tucker. Then she splits the
remaining treats between Bogey and Murphy, who get 3 treats each.
How many treats did Jasmine start with? Solve the problem by working
backward, and by writing and solving an equation.
Answer:
if bogey and murphy each get 3 treats and tucker gets 4 then the total is 3+3+4=10
Step-by-step explanation:
Jasmine starts with 10 treats.
What is Unitary Method?The unitary technique involves first determining the value of a single unit, followed by the value of the necessary number of units.
For example, Let's say Ram spends 36 Rs. for a dozen (12) bananas.
12 bananas will set you back 36 Rs. 1 banana costs 36 x 12 = 3 Rupees.
As a result, one banana costs three rupees. Let's say we need to calculate the price of 15 bananas.
This may be done as follows: 15 bananas cost 3 rupees each; 15 units cost 45 rupees.
Given:
She gives 4 treats to Tucker.
Then splits the remaining treats between Bogey and Murphy, who get 3 treats each.
So, if bogey and murphy each get 3 treats and tucker gets 4 then
= 3+3+4
=10 treats
Hence, at beginning Jasmine starts with 10 treats.
Learn more about Unitary Method here:
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Which expression is equivalent to the expression
(2x + 4)(x - 6)?
help quick!! please i have 10 minutes!!
Sorry it's been longer than 10 min I hope this is accurate.
Will give brainiest answer
Answer:
I'm pretty sure it's a.....
The answer is A
Step-by-step explanation:
common sense
BRAINLIEST WILL BE AWARDED!!!!!!!!!!!!!!!!!
Answer:
1. = 5
2. = -7
3. = -4
Can someone help me with this question for geometry.
Thanks will mark brainliest
Answer:
none of the above ,,,,,,,
what equation equivalent to 4x - 6y = 12
Answer:
12+6y=4x
Step-by-step explanation:
Answer:
y=2/3x−2
Step-by-step explanation:
If James bought 5/12 of cherries and 1/3 of cranberries. How much fruit did he buy. Write your answer in simplest form.
Answer:
The correct result would be 3/4 of a pound of dried fruit.
at a local coffee shop, about 20% of the customers who buy coffee also buy a pastry. if they have 300 customers buying coffee about how many pastries should they expect to sell?
Answer:
60
Step-by-step explanation:
answer this question JUST FOR POINTS this is not a real question (2+2)
Answer:
4 I think I could be wrong hahaha
Please helppp.
Simplify an expression for the perimeter and
an expression for the area of the rectangle
shown
Answer:
perimeter: 8x + 3 + 8x + 3 + 5 + 5=16x + 16
Area: 5(8x+3)=40x+15
Will make you brainpower first person who answers correctly in major need of help!
Answer:4 and 35
Step-by-step explanation:
Am from the future
The extremes are 4 and 35.
What is extremes?The extremes are the values of the proportion that are furthest apart when written in ratio form using a colon. For example: In the proportion a : b = c : d, ‘a’ and ‘d’ are the extremes.
In general, four numbers are said to be in proportion, if the ratio of the first two quantities is equal to the ratio of the last two. In general, the symbol for representing a proportion is “: :”
(i) The numbers a, b, c and d are in proportional if the ratio of the first two quantities is equal to the ratio of the last two quantities, i.e., a : b : : c : d and is read as ‘a is to b is as c is to d’. The symbol ‘ : : ‘ stands for ‘is as’.
(ii) Each quantity in a proportion is called its term or its proportional.
(iii) In a proportion; the first and the last terms are called the extremes; whereas the second and the third terms are called the means.
If four numbers a, b, c and d are in proportional (i.e., a : b : : c : d), then a and d are known as extreme terms and b and c are called middle terms.
(v) The fourth term of a proportion is called fourth proportional.
Given:
4/7 = 20/35
Now, by the definition of extremes
the first and the last term is extremes
So, 4 and 35 are the extremes.
Learn more about proportion here:
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What is (6+4) (-12) using the Distributive Property?
Answer:
multiply -12 first by 6 and then by 4
Karen flies her Cessna Skyhawk aircraft 360 miles with a tailwind of 10 miles per hour in the same time it could fly 300 miles with a headwind of 10 miles per hour. Find the speed of the aircraft.
Answer:
The speed of the aircraft is 126.667 miles per hour.
Step-by-step explanation:
Let suppose that aircraft travels at constant speed. From Mechanical Physics, we understand speed as travelled distance divided by time. In this case, the absolute speed of the aircraft is the sum of wind speed and speed of the aircraft relative to wind. That is:
Tailwind (Wind flows in the same direction of aircraft)
[tex]t = \frac{s_{T}}{v_{W,T}+v_{A/W,T}}[/tex] (Eq. 1)
Headwind (Wind flow in the direction opposite to aircraft)
[tex]t = \frac{s_{H}}{v_{W,H}+v_{A/W,H}}[/tex] (Eq. 2)
Where:
[tex]s_{T}[/tex], [tex]s_{H}[/tex] - Travelled distances on tailwind and headwind conditions, measured in meters.
[tex]v_{W,T}[/tex], [tex]v_{W,H}[/tex] - Tailwind and headwind speeds, measured in meters per second.
[tex]v_{A/W,T}[/tex], [tex]v_{A/W,H}[/tex] - Relative speeds of aircraft relative to tailwind and headwind, measured in meters per second.
We proceed to equalize both expressions to eliminate time:
[tex]\frac{s_{T}}{v_{W,T}+v_{A/W,T}} = \frac{s_{H}}{v_{W,H}+v_{A/W,H}}[/tex] (Eq. 3)
If we know that [tex]s_{T} = 360\,mi[/tex], [tex]s_{H} = 300\,mi[/tex], [tex]v_{W,T} = 10\,\frac{mi}{h}[/tex], [tex]v_{W,H} = -10\,\frac{mi}{h}[/tex] and [tex]v_{A/W,T} = v_{A/W,H}[/tex], then:
[tex]\frac{360}{v+10} = \frac{300}{v-10}[/tex]
The relative speed of the aircraft is now cleared:
[tex]360\cdot (v-10)=300\cdot (v+10)[/tex]
[tex]360\cdot v-3600 = 300\cdot v +3000[/tex]
[tex]60\cdot v = 7600[/tex]
[tex]v = 126.667\,\frac{mi}{h}[/tex]
The speed of the aircraft is 126.667 miles per hour.
Becky and claire went trick or treating.At the end of the night ,they combined their candy and found they each had four large candy bars.Becky ate two candy bars and clair ate one
Answer:
Well, You possibly did all the math depending on the question. But if it was subtraction that means there's one candy bar left
step-by-step explanation:
I hope this helped in any way!
15.9687194227 rounded to the nearest tenth
Answer:
i think its 16
Step-by-step explanation:
Answer:
16.0
Step-by-step explanation:
Nearest tenth place value is the digit directly to the right of the decimal point. Locate the tenth place value. It will be underlined and bolded:
15.968194227
Look at the number directly right of the given term. Note that:
If the digit is 5 or greater, round up.
If the digit is 4 or less, round down.
Since the digit is 6, round up.
15.968194227 rounded to the nearest tenth is 16.0
~
will mark as brainlyestWhat Is The Square Root Of 4?
Answer:
2
Step-by-step explanation:
Hope you don't need to summarize:) if so I will do it for you!